Many life forms, especially those with hard shells or stony skeletons (like LPS & SPS corals) coraline algae & more are greatly affected by Alkalinity or KH levels. It works together with Calcium for animals to build their skeletons. We want to have a level 7-11 dKH. Red Sea Reef Foundation B is a liquid additive that will easily increase your DKH/Alkilinty levels. Not sure what your levels are? Be sure to purchase my Red Sea Foundation Pro Test kit & find out!